Purpose: To evaluate the toxicity profile and pharmacological properties of oral CP-547,632 alone and in combination with paclitaxel and carboplatin administered every 3 weeks, and to assess efficacy as measured by the objective response and progressive disease rates of oral CP-547,632 administered in combination with paclitaxel and carboplatin.
Patients and methods: Patients with stage IIIB/IV or recurrent non-small cell lung cancer receiving first-line chemotherapy were treated with oral daily CP-547,632 in combination with paclitaxel 225 mg/m(2) and carboplatin AUC = 6 every 3 weeks. Pharmacokinetics parameters for CP-547,632 and paclitaxel were determined independently and during co-administration.
Results: Seventy patients were enrolled and 68 patients were treated, 37 in phase 1 and 31 in phase 2 (14 with the combination and 17 with chemotherapy alone). Dose-limiting toxicity of CP-547,632 250 mg by mouth daily in combination with paclitaxel and carboplatin was grade 3 rash and grade 3 diarrhea despite medical intervention. CP-547,632 did not significantly affect the pharmacologic profiles of paclitaxel and carboplatin. No subject had CR. In phase I, seven subjects (22.6%) had a confirmed partial response. In phase II, four subjects (28.6%) receiving CP-547,632 plus chemotherapy had a confirmed partial response. In the phase II chemotherapy alone group, four subjects (25%) had a confirmed partial response.
Conclusion: The combination of CP-547,632 and paclitaxel and carboplatin was well-tolerated at doses up to 200 mg by mouth daily. Dose-limiting toxicity of CP-547,632 at 250 mg consisted of diarrhea and rash. CP-547,632 did not increase the objective response rate to chemotherapy alone in patients with advanced non-small cell lung cancer.